1. Field of the Invention
This invention relates to a closed door circuit breaker racking extension which may be used for racking-in or racking-out a circuit breaker in a switchgear cell from outside a closed cell door.
2. Description of the Related Art
Switchgear equipment such as circuit breakers, etc. are positioned within cells formed in an enclosure or cabinet with the cells being closed by a cell door. To install a circuit breaker in a cell, the cell door is opened and the circuit breaker is positioned on and secured to a circuit breaker racking device. Most racking devices include a drive shaft or threaded actuator shaft which is rotated to move the racking device and circuit board thereon inwardly into the cell for connecting the circuit board to its associated electrical equipment. It is extremely dangerous to rack-in the circuit breaker into its operative position while the cell door is open due to the danger of an arc-fault explosion occurring when the circuit breaker is being electrically connected to its associated electrical equipment. In some cases, an actuator shaft is inserted through an opening in the cell door for connection to the drive shaft of the racking device. If an arc-fault explosion occurs, dangerous gases and debris may be blown outwardly through the opening in the cell door to cause injury to the person installing the circuit breaker. In some cases, the drive shaft of the racking device is operated by a remote control. The danger of gases and debris passing outwardly through the opening in the cell door upon an arc-fault explosion still exists.